▼ Oilseed radish (Raphanus sativus) is identified as a potential cool season cover and energy crop for Georgia. Oilseed radish oil is extracted from seed and transesterified to biodiesel. The properties and engine performance of oilseed radish biodiesel are shown to be comparible with No. 2 diesel and other common biodiesel fuels. The economics of a potential oilseed radish crop are examined on a per acre basis accounting for biodiesel value, byproduct meal and glycerin value, and also the agronomic value of nematode control.
Advisors/Committee Members: K.C. Das.

▼ Biofuels that share similarities to petro-diesel regarding combustion properties have received renewed attention. Triacylglycerols (TAG) comprise the main compound in plant oil seed crops and animal fats that is used for biodiesel. In senescent leaves, TAGs are the most abundant pool of lipids. TAGs contain higher levels of fatty acids than are found in chloroplast membranes. Synthesis of glucose from non-carbohydrate carbon substrates occurs via gluconeogenesis from the oxidation of TAGs into glucose, pyruvate, lactate, and glycerol. This study examines the effect gluconeogenesis inhibitors, such as sodium oxamate, could play in increasing oil accumulation in plants. Also, this study tests the efficacy of sodium oxamate in increasing TAG and membrane
lipids in Brassica napus. Several concentrations of sodium oxamate (control, (water with surfactant), 0.0005 mM, 0.005 mM, 0.05 mM, 0.5 mM) were applied to plant leaves. Oil was extracted by using chloroform/methanol (2:1) in accelerated solvent extraction. No oil bodies were observed in the leaves from the vegetative to the reproductive stages for each treated plant. Extracted oil from each plant was separated using thin layer chromatography (TLC) to determine if changes in lipid composition occurred in leaves. We concluded that sodium oxamate did not affect the oil accumulation in leaves of B.napus under the conditions tested. Further studies should be conducted with alternate species and varying surfactants to understand the role that sodium oxamate plays in
altering gluconeogenesis driven oil content.
Advisors/Committee Members: Hays, Dirk (advisor), Gentry, Terry (committee member), Ibrahim, Amir (committee member), Senseman, Scott (committee member).

► Pure glycerol and the crude waste glycerin byproduct of biodiesel production were tested as substrates for electricity production in single-chamber, air-cathode microbial fuel cells (MFCs)…
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▼ Pure glycerol and the crude waste glycerin byproduct of biodiesel production
were tested as substrates for electricity production in single-chamber, air-cathode
microbial fuel cells (MFCs) and in single-chamber microbial electrolysis cells
(MECs), using pure and mixed microbial cultures as anode biocatalyst. Current
densities of 0.40 A/m² and 0.13 A/m² were generated on 50 mM glycerol in aircathode
MFCs by pure cultures of Shewanella oneidensis MR-1 and
Rhodopseudomonas palustris ATCC 17001, respectively, after aerobic flask culture.
A mixed culture of bacteria originally derived from wastewater generated
higher current and power densities than any of the pure cultures and, at 10 mM
glycerol, achieved an average maximum power density of 2.70 ± 0.15 W/m² anode
surface area (47.8 ± 2.6 W/m³ reactor volume) at a current density of 7.66 ± 0.21 A/m²
anode surface area. At an optimal fixed external resistance of 210 Ω the mixed culture
MFC followed Michaelis-Menten saturation kinetics, resulting in a Km of 2.92 mM
glycerol and a theoretical Vmax of 0.437 volts. Coulombic efficiencies decreased
linearly with increased glycerol concentration.
Power was generated by mixed culture MFCs from raw waste glycerin byproduct of biodiesel manufacture both with and without methanol, and with and without potassium salts and soaps. Maximum volumetric current and power densities achieved on waste glycerin (147.7 A/m³ and 56.8 W/m³) were greater than those reported in previous studies, but CE values (10-17.6%) were significantly lower, likely due to losses from aerobic respiration in the micro-aerobic environment of an MFC. Decreases in maximum current density of 43.4% and 65.1% were observed over successive batches of waste glycerin with and without methanol, respectively. Decreases in performance were attributed primarily to the presence of potassium salts, soaps, FFAs, and residual catalyst in the waste glycerin, rather than to methanol. MFCs operating on waste glycerin from which these salts and soaps had been precipitated did not show the same pattern of decreasing maximum current density over multiple batches.
Cathode potentiometry indicated a decrease in cathode performance after development of a thick biofilm on the cathode surface during batches of glycerol and glycerin. The best fit lines of cathode potential vs. current density before and after cathode biofilm development during batches of glycerol were used to predict a 30.2% decrease in power density, a result that corresponded well to the 25.7% decrease in power density that was actually observed.
Single chamber, membrane-free mixed culture MECs were able to produce hydrogen successfully from both pure glycerol and waste glycerin byproduct from biodiesel manufacture. At an applied voltage of 0.6 V, a maximum current density of 7.5 ± 0.4 A/m² (238.6 ± 12.7 A/m³) was observed, the highest reported current density for a MEC operating on glycerol. Maximum current densities on 0.5% waste glycerin with and without methanol were 0.1-0.2 A/m² less than…
Advisors/Committee Members: Liu, Hong (advisor), Chaplen, Frank (committee member).

This work was carried out to improve the Transesterification Double Step Process (TDSP) methodology for biodiesel production. To achieve the process’ improvement, the influence of eight parameters over the conversion of triglycerides into methyl esters were studied, which are: alcohol/oil and catalyst/oil molar ratio, reaction temperature and time, for both steps (basic and acid catalysis). Defined the optimum amounts to be used, biodiesel were synthesized using the modified process from three different oils: soybean, linseed and waste cooking. The conversion was calculated by means of Hydrogen Nuclear Magnetic Resonance spectroscopy. To assess the quality of produced biodiesel a set of sixteen physical-chemical analyses were carried out in accordance with an ANP methodology. As the product without treatment did not reach the specifications in most of the parameters, three purification processes were studied: washing with water, Celite® adsorption and rice hull ash adsorption. Concurrently, the data obtained from the syntheses in the laboratory were used for the design of a pilot plant accordingly to the proposed…

► The dwindling resources of fossil fuels coupled with the steady increase in energy consumption have spurred research interest in alternative and renewable energy sources. Biodiesel…
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▼ The dwindling resources of fossil fuels coupled with the steady increase in energy
consumption have spurred research interest in alternative and renewable energy sources.
Biodiesel is one of the most promising alternatives for fossil fuels. It can be made from
various renewable sources, including recycled oil, and can be utilized in lieu of
petroleum-based diesel. To foster market competitiveness for biodiesel, it is necessary to
develop cost-effective and technically sound processing schemes, to identify related key
design criteria, and optimize performance.
The overall goal of this work was to design and optimize biodiesel (Fatty Acid
Methyl Ester ?FAME?) production from vegetable oil. To achieve this goal, several interconnected
research activities were undertaken. First, a base-case flow sheet was
developed for the process. The performance of this flow sheet along with the key design
and operating criteria were identified by conducting computer-aided simulation using
ASPEN Plus. Various scenarios were simulated to provide sufficient understanding and
insights. Also, different thermodynamic databases were used for different sections of the
process to account for the various characteristics of the streams throughout the process.
Next, mass and energy integration studies were performed to reduce the consumption of
material and energy utilities, improve environmental impact, and enhance profitability.
Finally, capital cost estimation was carried out using the ICARUS Process Evaluator
computer-aided tools linked to the results of the ASPEN simulation.
The operating cost of the process was estimated using the key information on
process operation such as raw materials, utilities, and labor. A profitability analysis was
carried out by examining the ROI (Return of Investment) and PP (Payback Period). It
was determined that the single most important economic factor is the cost of soybean oil,
which accounted for more than 90% of the total annualized cost. Consequently, a sensitivity analysis was performed to examine the effect of soybean oil cost on
profitability. It was determined that both ROI and PP quickly deteriorate as the cost of
soybean oil increases.
Advisors/Committee Members: El-Halwagi, Mahmoud (advisor), Curry, Guy (committee member), Mannan, Sam (committee member).

Biofuels are liquid or gaseous fuels obtained from biomass newlineNumber of biofuels have been obtained from various sources but a good newlinebiofuel must be a…
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Biofuels are liquid or gaseous fuels obtained from
biomass newlineNumber of biofuels have been obtained from various
sources but a good newlinebiofuel must be a from a renewable source
b environmental friendly newline c biodegradable d should have a
shorter CO2 cycle and most importantly newline e sustainable The
diminishing source of fossil fuels rapid increase in toxic
newlinepollutants and increase in petroleum price have led the
researchers all over the newlineworld to focus research in the
areas of alternative fuels Plant oils such as newlinecotton soybean
canola and palm oil have been extensively studied in recent
newlineyears for the production of biofuels newlineTechniques such
as transesterification biodiesel pyrolysis higher
newlineHydrocarbons catalytic cracking lower and branched
hydrocarbons and newlinefermentation bioethanol have been reported
for the conversion of vegetable newlineoils into biofuels But the
techniques mentioned above have both merits and newlinedemerits
Herein we report a scarcely attempted catalytic cracking technique
newlinefor the conversion of vegetable oils into biofuels newline
newline

Most of the energy consumed worldwide comes from oil, coal and natural gas. These sources are limited, so alternative sources are needed and the search…
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Most of the energy consumed worldwide comes from oil, coal and natural gas. These sources are limited, so alternative sources are needed and the search for such sources is very important. Vegetable oils have been mentioned as likely replacements for diesel fuel since the beginning of last century by having physical and chemical characteristics that could be close or suitable for a diesel engine. They can be used in diesel engines with or without processing. Since January 1st of 2010 was established the addition of 5% biodiesel to diesel in Brazil. The transformation of vegetable oil into biodiesel refers only to better adapt to the engine. The Brazilian Biodiesel Production Chain currently has no regulations regarding the matrix to be used, and is currently regulated by the availability of raw materials. There is still no standardized method for analyzing biodiesel in diesel. Pure biodiesel is analyzed first and then added to diesel. In this work, eight multivariable calibration models based on middle-infrared spectroscopy were developed in order to determine the content of biodiesel in diesel fuel (binary blends), in the range of 1 to 20% v/v, generically called BX. Esters (methylic and ethylic) made with soybean, corn, sunflower seed oils and used soybean frying oil were used to prepare the blends with conventional diesel. Results indicated that partial least squares (PLS) models based on MID infrared spectra were proven suitable as practical analytical methods for predicting biodiesel content in conventional diesel blends in the volume fraction range from 1% to 20%. PLS models were validated by independent prediction set and the RMSEPs (Root Mean Square Errors of Prediction) were estimated as low as 0,2266; RMSECs (Root Mean Square Errors of Calibration) were estimated as low as 0,1532. Linear correlations were observed for predicted vs. observed values plots with correlation coefficient (R) greater than 0,999. Additionally, the average preview errors found were less than 2,21%.

This work dealt with the transesterification reaction as the chemical process to obtain biodiesel via either methyl or ethyl routes, using oils from corn or soybean grains. The thermal expansion coefficients were determined for both methyl and ethyl biodiesels, be from corn oil or soybean oil. Specific mathematical models were proposed to predict values of the thermal expansion for each of these biodíesels. It is remarkable the found difference between predictable values as obtained from the proposed mathematical model (algorithm) for the biodiesels, even if compared to the standard EN 14214 recommendation. The optimal set of reaction conditions for the transesterification process via ethylic route was more specifically investigate by using the following variables: temperature, speed, reaction time, type of catalyst, concentration of catalyst and molar ratio. The latter two were found to be operationally more important. The transesterification reaction with corn oil was found to be a robust process, in the sense that small variations on its condition do not significantly affect the whole yield: the tolerated range of values for the catalyst concentration is 1.56 0.25% (m/m) whereas for the molar ratio (ethanol: oil) it is 10.9:1 1. Conditions of maximum yield for this reaction are (i) type of catalyst: potassium hydroxide; (ii) catalyst concentration: 1.56 % (w/w); (iii) molar ratio (ethanol: oil): 10.9:1; (iv) temperature: 55 0C; (v) reaction time: 60 minutes and (vi) rotation: 100 rpm.

► The production of biodiesel from fish oil was carried out using enzymatic transesterification. The effects of the oil: alcohol molar ratio (1:1, 1:2, 1:3, 1:4…
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▼ The production of biodiesel from fish oil was carried
out using enzymatic transesterification. The effects of the oil:
alcohol molar ratio (1:1, 1:2, 1:3, 1:4 and 1:5), alcohol type
(methanol and 2-butanol), reaction temperature (35, 40, 45 and
50ºC), reaction time (4, 8, 12 and 16 h) and solvent type (solvent
and solvent-free) on the biodiesel conversion yield using Candida
antarctica (Novozyme 435) and experimental enzyme (NS88001) were
investigated. The biodiesel conversion yield increased when the
reaction temperature was increased from 35 to 40ºC and then
decreased when the reaction temperature was further increased to 45
and 50ºC, respectively. Increasing the oil: alcohol molar ratio
from 1:1 to 1:4 increased the biodiesel conversion yield which then
decreased when the oil: alcohol molar ratio was further increased
to 1:5. The highest biodiesel conversion yield was obtained after
16 h at the oil: alcohol molar ratio of 1:4 and the reaction
temperature of 40ºC using Novozyme 435 and NS88001 individually and
in combination. No reaction was observed at the oil: alcohol molar
ratio of 1:1 for Novozyme 435 enzyme and at 1:1 and 1:2 oil:
alcohol molar ratios for NS88001 enzyme in a solvent- free system.
The highest biodiesel conversion yield from Novozyme 435 (80.24%)
was observed with 2-butanol, the highest biodiesel conversion yield
from NS88001 (74.34%) was observed with methanol and the highest
biodiesel conversion yield from the combination of enzymes
(Novozyme 435 and NS88001) lipase (82.37%) was observed with
2-butanol. The stability of the enzymes Novozyme 435 and NS88001
individually and in combination slightly decreased after 10 cycles
and completely stopped after 20-30 cycles.
Advisors/Committee Members: N/A (external-examiner), DR. MARK GIBSON (graduate-coordinator), DR. SUZANNE M. BUDGE (thesis-reader), DR. ABDEL GHALY, DR. SU-LING BROOKS (thesis-supervisor), Not Applicable (ethics-approval), No (manuscripts), No (copyright-release).

…17
Figure 3.4. Process flow schematic for production of biodiesel from fish oil by alkali… …104
Figure 5.21. Effect of reaction time on the conversion yield of biodiesel by a… …112
Figure 5.24. Biodiesel yield of Novozyme 435, NS88001 and Combination of enzymes
(… …ABSTRACT
The production of biodiesel from fish oil was carried out using enzymatic… …free) on the biodiesel conversion yield using Candida
antarctica (Novozyme 435)…

► ﻿Because of the depletion of the world’s petroleum reserves and the increasing environmental concerns, biodiesel, as a low-emission renewable fuel and one of the best…
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▼ ﻿Because of the depletion of the world’s petroleum
reserves and the increasing environmental concerns, biodiesel, as a
low-emission renewable fuel and one of the best substitutes for
petro-diesel fuel, has attracted great public interest over the
past decades. At present, camelina oil has been considered as a
low-cost feedstock for biodiesel production because of its high oil
content and environmental benefits. In the present study, the
optimization of biodiesel production and purification from camelina
oil is studied extensively in order to maximize the biodiesel
yield. The orthogonal array design is used to optimize the
biodiesel production and four relevant process conditions for
affecting biodiesel yield are investigated: methanol to oil ratio,
catalyst concentration, reaction time and temperature. For the
optimization study on biodiesel purification, five commonly used
washing methods are also investigated: cold deionized water
washing, hot deionized water washing, phosphoric acid washing,
ultrasonic assisted washing, and magnesol washing. The optimization
study, based on traditional mechanical stirring process, reveals
that the decreasing ranking of significant factors for biodiesel
production is catalyst concentration > reaction time >
reaction temperature > methanol to oil ratio. The maximum
biodiesel yield is found at a molar ratio of methanol to oil of
8:1, a reaction time of 70 min, a reaction temperature of 50℃, and
a catalyst concentration of 1 wt.%. After testing the fuel
properties of the final product, the optimized biodiesel meets the
relevant requirements of the biodiesel standards and thus can be
used as a qualified fuel for diesel engines. The optimization
study, based on ultrasonic-assisted transesterification process,
reveals that the maximal fatty acid methyl ester yield of the final
biodiesel product is obtained under a methanol to oil molar ratio
of 8:1, catalyst concentration of 1.25 wt.%, reaction time of 50
min and reaction temperature of 55 ℃. Compared with traditional
mechanical stirring production process, ultrasonic-assisted
transesterification process improves the biodiesel production since
it could reduce the production cost and save energy. For the
optimization study on biodiesel purification, the fatty acid methyl
ester yield of the final biodiesel product, energy consumption and
economic costs of different washing methods are compared. The
comparisons indicate that the ultrasonic assisted washing method is
the best method for biodiesel purification, when energy consumption
and operation costs are considered. A preliminary kinetics study of
transesterification reaction of camelina oil is carried out. After
discussing four cases for overall reaction, a third-order reaction
mechanism was proposed to fit the experimental data better because
of the highest coefficient of determination. Based on the best-fit
plot, the rate constants and activation energy are also determined.
To sum up, the present research focuses on the optimization of
biodiesel production and purification from…
Advisors/Committee Members: Leung, YC.

The goal of this work is the research in the use of an industrial waste (animal fat) in the biodiesel production with methanol and alkaline catalyst. Although the bovine fat is not considered as renewable source of energy, if compared to oleaginous ones, but an industrial residue, the interest in its use in the of biodiesel has increased in the last years. Besides these advantages, when it is made use of animal fat, an important environmental aspect is the use of a residual raw material as biofuel that, although it is not considered a renewable source, its use plays an important role in the reduction of pollution. The study initially was made in a laboratory scale and after this, it was constructed a semi industrial pilot-plant with a capacity of 800 L day-1 of biodiesel (with methanol and potassium hydroxide), being also obtained a biodiesel that was approved according to the norms of the ANP Resolution 42. The produced biodiesel was tested in blends with 20%, 30% and 40% of biodiesel in mineral diesel were used in automotive motors (truck and car) with highly satisfactory…

In our society, energy and environmental questions are becoming important issues, « green » alternatives to conventional processes are in continuous development. In particular, works on biodiesel synthesis from vegetable oil have strongly increase during these last 20 years. The use of pure vegetable oil from seeds for human feed being critical, substitute products are used for biodiesel synthesis. Withnin this framework,this PhD thesis treats on the synthesis of biodiesel from used vegetable oil by enzyme methods .The transesterification reaction has been throughly studied as well on reaction conditions (temperature, enzyme/substrate ratio, kinetic reaction), as on the type of enzyme (nature of the organism of origin of the enzyme, in solution or immobilized) or on reactor type (BSTR, PBR or CSTR). In some conditions, the conversion has been total (> 99 %), allowing for atmospheric emission testing of an unrefined biofuel. Separation of the different constituents of biofuel by membrane process has been carried out in order to obtain a biodiesel made up only of esters, ethanol and glycerol ; these last two constituents has been removed by evaporation and decantation. The product’s environmental footprint has been calculated by the life cycle assessment method and compared with the impact of the first generation biofuels.

► Inductively coupled plasma atomic emission spectrometry (ICP-AES) has emerged as a dominant spectroscopic technique for the determination of metals in a plethora of sample types.…
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▼ Inductively coupled plasma atomic emission spectrometry (ICP-AES) has emerged as a dominant spectroscopic technique for the determination of metals in a plethora of sample types. The bulk of the interest has been placed on trace metal analysis, and the analysis of nonmetals has been gaining increased interest since the 1980's. In this work, an inductively coupled plasma atomic emission spectrometer is used for the determination of nonmentals in different sample types. The present research covers three projects using ICP-AES to detect nonmetals by monitoring their emission in the vacuum ultraviolet region of the electromagnetic spectrum.

Jatropha curcas L. as a raw to produce biodiesel presents a promising alternative because of the perennial production of its fruits and a high oil concentration on its seeds. The mechanical extraction of the oil yielded 38% while the chemical extraction yielded 44.8% but the oil chemically extracted presented a higher acidity index, in relation to the mechanical extracted oil, factor that interferes in the transesterification reaction. The chromatographic data showed higher concentration of oleic acid (C 18:1) with 35,89% and linoleic acid (C 18:2) with 44,45%. The ethyl biodiesel was obtained through alcaline transesterification (KOH) and the 5%, 10% and 20% (m/m) biodiesel/diesel mixtures were prepared and then submitted to storage for 120 days, at room temperature. The results of RMN 1H and medium infrared characterized the ethyl biodiesel and its mixtures (B5, B10 and B20). The oxidative behavior of ethyl biodiesel and its mixtures were monitored through UV-Visible spectroscopy. The PetroOXY (OITB100= 52, 48, 35, 28 min) and P-DSC (HPOITB100= 41,30; 22,63; 7,72 min) techniques monitored the pure biodiesels oxidative process and the results obtained indicate that oxidation occurred through the long period of storage. The cold hydrodynamic and flow properties confirmed the oxidative process, where was observed a slightly increase in viscosity,…

This work aims at contributing to the knowledge of energy consumption in a typical plant of biodiesel production. The energy consumed in the production of fuel must be compatible to the one available in its updating. Therefore, the theoretical thermal energy involved in the production of a biodiesel mass unit in kJ/kg has been evaluated compared to its lower heat value (LHV). To the unitary operations of this process, the balance of materials and energy has been applied as a method to calculate the thermal charge in each operation to determine the energy consumption. To do so, it was necessary to find representative molecular formulas for both oil and biodiesel, with calculations based on the molar mass of each. The application of the calculations of the enthalpy balance in some unitary operations depended on the values of the formation enthalpies of oil and biodiesel, which have been calculated through the principle of Hess, by means of the reactions of combustion. The consumption of steam from the biodiesel plant has been calculated through the steam mass consumed all over the process being compared to the necessary consumption of biodiesel to produce this steam. The analyzed process consumes 25% of the biodiesel produced to generate its heating necessities, confirming the use of biodiesel as fuel in energy terms.

Much is said about the origin of coffee and the habit of consuming it. For many centuries, its use was restricted to the Muslim world, and the Dutch were the first to get seedling and to try to grow them. Because of unfavorable weather across Europe, the seedlings were sent for testing in Central America and soon production occurred in a large scale. In 1727 coffee arrived in Brazil and became the main export of the country. Brazil is also a major consumer of coffee and its residue is a daily domestic waste in almost all homes, shops, bars and restaurant, and its final destination will be the open dumps and landfills Even though it is not an oleaginous grain the roasted coffee contains about 10 to 15% of saturated and unsaturated fatty acids. Vegetable oils from seeds of plants such as soybeans, castor beans, peanuts, palm oil among others, are the most common sources of triglycerides. Triglycerides have been considered a viable and interesting option as a renewable energy source with the potential to partially or totally replace the diesel fuel derived from petroleum. The alternative energy is present in our daily lives. In the Chemistry class we can involve environmental and energy issues, from the extraction of essential oil that exists in coffee ground, which contains about 9 to 11% of saturated and unsaturated fatty acids, a considerable value compared to oleaginous grains and finds a destination to it, the biodiesel. Thus stimulating creativity…

► Based on the GT-Power software, an engine cycle simulation for a biodiesel fueled direct injection compression ignition engine was developed and used to study its…
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▼ Based on the GT-Power software, an engine cycle simulation for a biodiesel
fueled direct injection compression ignition engine was developed and used to study its
performance and emission characteristics. The major objectives were to establish the
engine model for simulation and then apply the model to study the biodiesel fueled
engine and compare it to a petroleum-fueled engine.
The engine model was developed corresponding to a 4.5 liter, John Deere 4045
four-cylinder diesel engine. Submodels for flow in intake/exhaust system, fuel injection,
fuel vaporization and combustion, cylinder heat transfer, and energy transfer in a
turbocharging system were combined with a thermodynamic analysis of the engine to
yield instantaneous in-cylinder parameters and overall engine performance and emission
characteristics.
At selected engine operating conditions, sensitivities of engine performance and
emission on engine load/speed, injection timing, injection pressure, EGR level, and
compression ratio were investigated. Variations in cylinder pressure, ignition delay, bsfc,
and indicated specific nitrogen dioxide were determined for both a biodiesel fueled
engine and a conventional diesel fueled engine. Cylinder pressure and indicated specific
nitrogen dioxide for a diesel fueled engine were consistently higher than those for a
biodiesel fueled engine, while ignition delay and bsfc had opposite trends. In addition,
numerical study focusing on NOx emission were also investigated by using 5 different
NO kinetics. Differences in NOx prediction between kinetics ranged from 10% to 65%.
Advisors/Committee Members: Caton, Jerald A. (advisor), Jacobs, Timothy J. (committee member), Capareda, Sergio (committee member).

►Biodiesel is a fuel obtained from vegetable oils, such as soy, castorbean, among others. The monoester of fatty acid of these oils have chains with…
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▼Biodiesel is a fuel obtained from vegetable oils, such as soy, castorbean, among others. The monoester of fatty acid of these oils have chains with mono, di and tri double connections. The presence of these insaturations are susceptible to oxidization. Antioxidants are substances able to prevent oxidization from oils, fats, fat foods, as well as esters of Alquila( biodiesel). The objective of this work is to summarize a new antioxidant from the Cashew Nut Shell Liquid (CNSL) using the electrolysis technique. A current of 2 amperes was used in a single cell of only one group and two eletrodos of stainless steel 304 in a solution of methanol, together with the eletrolits: acetic acid, sodium chloride and sodium hydroxide, for two hours of agitation. The electrolysis products are characterized by the techniques of cromatography in a thin layer, spectroscopy of infrared and gravimetric analysis. The material was submitted to tests of oxidative stability made by the techniques of spectropy of impendancy and Rancimat (EN 14112). The analyses of characterization suggest that the polimerization of the electrolytic material ocurred. The application results of these materials as antioxidants of soy biodiesel showed that the order of the oxidative stability was obtained by both techniques used
Advisors/Committee Members: Santos Júnior, José Ribeiro dos (advisor), CPF:06636519304 (advisor), http://lattes.cnpq.br/1444230896818008 (advisor).

The present work aims the study of structural and thermodynamic properties for process involving triglycerides (TG), fatty acid esters (EAG) and biodiesel through theoretical and…
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The present work aims the study of structural and thermodynamic properties for process involving triglycerides (TG), fatty acid esters (EAG) and biodiesel through theoretical and chemometrical methodologies. The study of the transesterification reaction of triglycerides (TG) using cyclodextrin (CD) as a potential catalyst were also carried out. Initially, through a Box-Behnken 34 factorial design, the effects of the variables involved in molecular dynamics simulation (MD) of inclusion compounds formed between trilaurylglyceride (TLG 12:0) and α-CD were evaluated. The results lead to an appropriated MD heating protocol for the treatment of [email protected] systems with specific values for the variables involved in the process: time of heating (W), equilibrium time (E), time step of the dynamics (S) and dielectric constant of the medium (C). Starting from the best protocol, MD studies were developed contemplating inclusion complexes formed between TG models used the biodiesel synthesis trilaurylglyceride (TLG 12:0), tripentadecanoylglyceride (TPDG 15:0), trihexadecanoylglyceride (THDG 16:0), triestearylglyceride (TESG 18:0), trioleylglyceride (TOG 18:1), trilinoleylglyceride (TLLG 18:2) e trilinolenylgliceride TLNG 18:3) and native α-CD and modified cyclodextrin (α-CD-NH2). The results pointed out a correlation between the stability of the [email protected]α-CD inclusion compounds and size and saturation degree of the triglyceridic included chain. The catalytic potential of CD the transesterification reaction of TG was also investigated through geometry optimization and vibrational harmonic frequencies calculations via DFT. The results show thermodynamic evidences for such proposal using α-CD as catalyst. Besides, theoretical infrared and Raman spectra were determined for some TG and EAG species, looking for the elucidation of possible methods capable to contribute for the experimental analysis of biodiesel. Some interesting fingerprints were noticed in the spectrum of saturated and unsaturated species, allowing the characterization of complex mixtures obtained in the biodiesel production

This work proposes the use of chitosan as a catalyst in the transesterification of soybean oil with methanol. The results showed that pure chitosan had not activity for the reaction of transesterification, did not exceed 6% of income. However, the same procedure with old oil obtained excellent income (68,6 0,54 %), which may have occurred in a possible acidification of chitosan by the hydrolysis of triglycerides. Thus, tests were made of chitosan previously acidified with HCl, in new oil, which has produced excellent activities. After several tests to determine the best conditions of reaction, a maximum yield of 69,4 0,93 % was obtained with 0,1 mol/L as the best concentration of HCl to acidify 1,0 g of chitosan; 0,15 g as the best amount as a catalyst to react with 10 g of soybean oil and 1,5 g of methanol; 2 h as the best time of reaction. Finally, was made the recycling and reuse of the catalyst, which showed active for the recycles reactions and, despite the decrease in income, can be reused some times. This alternative catalytic system is of easy application, presents low-cost, greener, can be reused, presenting a better utilization of natural resources and mainly by the social appeal of wider application of chitosan for poor riverine communities.

The mixing of biodiesel and petroleum diesel is being widely used as an attempt to reduce the emissions of sulfur compounds. These compounds are responsible for pollution, causing several diseases, as some breath problems. Sulfur compounds cause car catalyst poisoning and deactivation of processing, contributing with undesirable emissions of other toxic compounds. The goal of this work was to identify sulfur compounds in diesel and in some biodiesel mixtures of different sources. Gas chromatography system coupled with FID (flame ionization detector) was the methodology initially employed, for adjustment of the operational conditions, since FID is a low selectivity detector capable of identifying sulfur compounds and the majority of hydrocarbons. For the sulfur identification, a selective detector for sulfur compounds was employed (SCD - sulfur chemiluminescence detector). After the initial tests realized in the lab, analyses were carried out in a typical Brazilian urban bus fleet, to quantify the presence of mercaptans. The bus was fueled with pure diesel and with different biodiesel blends (v v) of 2% (B2), 5% (B5), 10% ( B10) and 20% (B20). The samples were collected from a real bus in use. Obtained results showed that the addition of biodiesel decreases proportionally the presence of sulfur compounds

The simulation of three processes for biodiesel production has been developed: transesterified refined oil (P-01); transesterified residual oil pretreated (P-02) and finally the residual oil supercritical transesterification (P-03 ) from commercial software Hysys Â 7.3, using the NRTL thermodynamic model. The analysis of the total capital invested was performed by individual factors Guthrie and percentage method provided in Peters et al., (1991). The total invested capital obtained by the method of single factor Guthrie was 7,…